Membrane bioreactor commercialized

Yang, W.B., Cicek, N. and Ilg, J. (2006) State-of-the-art of membrane bioreactors Worldwide research and commercial applications in North America. Journal of Membrane Science, 270, 201-211. 

In recent years, membrane bioreactors, bioreactors combined with membrane separation unit have established themselves as an alternative configuration for traditional bioreactors. The important advantages offered by membrane bioreactors are the several different types of membrane modules, membrane structures, materials commercially available. Membrane bioreactors seem particularly suited to carry out complex enzymatic/microbial reactions and/or to separate, in situ, the product in order to increase the reaction efficiency. The membrane bioreactor is a new generation of the biochemical/chemical reactors that offer a wide variety of applications for producing new chemical compounds, for treatment of wastewater, and so on. 

Given the history and development of environmental engineering, with wastewater treatment in particular, as it is understood today, the membrane bioreactor is quite a recent invention. Commercialization and implementation of the technology has only been going on in the last couple of decades, and so, not surprisingly, MBR technology is still in a period of intense development [33]. The current M B R business... 

There have been numerous studies exploring the concept of membrane reactors. Many of them, however, are related to biotechnological applications where enzymes are used as catalysts in such reactions as saccharification of celluloses and hydrolysis of proteins at relatively low temperatures. Some applications such as production of monoclonal antibodies in a hollow fiber membrane bioreactor have just begun to be commercialized. 

The concept of coupling reaction with membrane separation has been applied to biological processes since the seventies. Membrane bioreactors (MBR) have been extensively studied, and today many are in industrial use worldwide. MBR development was a natural outcome of the extensive utilization membranes had found in the food and pharmaceutical industries. The dairy industry, in particular, has been a pioneer in the use of microfiltra-tion (MF), ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO) membranes. Applications include the processing of various natural fluids (milk, blood, fruit juices, etc.), the concentration of proteins from milk, and the separation of whey fractions, including lactose, proteins, minerals, and fats. These processes are typically performed at low temperature and pressure conditions making use of commercial membranes. 

In conclusion the published studies, so far, indicate that catalytic and electrochemical membrane reactors still face an uphill battle towards commercialization, with key concerns being membrane cost and reliability. Membrane bioreactors are already commercial, but membrane costs and reliability are still an area where improvements are needed. 

Tire Zee Weed submerged-membrane technology and equipment for the project was provided by GE Water. Process Technologies. GE s Zee Weed membrane bioreactor systems combine ultiafiltration technology w ith biological treatment for municipal, commercial and industrial wastewater treatment and water reuse applications,... 

Submerged membrane bioreactors are revolutionizing waste water treatment [108]. These units dramatically increase the capacity of waste water treatment ponds while simultaneously producing a higher quality water by using an ultrafiltration membrane to remove treated water from the mixed liquor suspended solids (MLSS) produced by biological treatment. Such process intensification is one of the hallmarks of applications where membrane processes have achieved commercial success (in addition to energy reduction and purification of labile compounds). 

In this section, several applications of membrane reactors on the commercial scale will be highlighted as well as some membrane-based processes that have potential for industrial application. Membrane-assisted esterifications and dehydrogenations will be discussed as well as the OTM process for the production of syngas. Additionally, typical membrane bioreactors such as used in the acy-lase process developed by Degussa AG, and membrane extraction systems such as the MPGM system and the Sepracor process are described. 

Microfiltration plants are also being installed in membrane bioreactors to treat municipal and industrial sewage water. Two types of systems that can be used are illustrated in Fig. 7.6. The design shown in Fig. 7.6(a), using a crossflow filtration module, was developed as early as 1966 by Okey and Stavenger at Dorr-Oliver [17]. The process was not commercialized for another 30 years for lack of suitable membrane technology. In the 1990s, workers at Zenon [15,16] in Canada and... 

The application of FO in recent years has expanded, not only in terms of installed capacity but also in the diversity of industries where the technology has been installed. Applications such as power generation, desalination, wastewater treatment (osmotic membrane bioreactor) and liquid food concentration are reported in the literature [4]. Commercial FO products are available for a variety of applications including personal water filtration and desalination, oil gas drilling water reclamation and landfill leachate treatment. 

Based on the list of literature reviewed in this chapter, it can be pointed out that a comparatively limited number of studies on cell-immobilized membrane reactors (Table 20.3) and extractive membrane bioreactors (Table 20.8) have been conducted. Studies only from certain research groups who targeted a limited number of recalcitrant compounds (predominantly phenol) are available. Currently only a few publications on these topics are published each year. This obviously is an impediment to progress in their scale-up. Major hurdles for a commercial realization of EMBRs are the cost of silicone rubber membranes and other difficulties associated with the scaling up process. The development and implementation of these systems at an industrial scale requires a broader as well as in-depth understanding of the core processes. 

Gomez, M., Murcia, M. D., Ortega, S., Barbosa, D. S., Vayd, G. aird Hidalgo, A. M. 2012. Removal of 4-chlorophenol in a continuous membrane bioreactor using different commercial peroxidases. Desalination and Water Treatment, 37,97-107. 

Abstract In this chapter, membrane bioreactors are described from an economic point of view. Economic analysis is a crucial stage in plant design, project and control and also requires an evaluation of the research, development and commercialization of the products and bioproducts. Such an analysis is focused here on membrane bioreactors and reactors, also taking into account the separation units such as micro-, ultra- and nano-flltration units that might be used as a downstream process or as pretreatment steps. The most important rules and parameters are first introduced. Some examples of application and case studies are also reported. 

Santos, A., Judd, S. (2010). The commercial status of membrane bioreactors for municipal wastewater. Separation Science and Technology, 45, 850—857. 

Sutton, P. - Membrane bioreactors for industrial wastewater treatment the state-of-the-art based on full scale commercial applications. WEFTEC, Los Angeles, USA, 2003... 

DeCarolis, J. F., Hirani, Z., Adham, S. S., Tran, N., and Lagos, S. (2006). Commercially available membrane bioreactor systems. In S. S. Adham (Ed.), Proceedings of Short Course on Membrane Bioreactors. National Water Research Institute, Anaheim, pp. 11-17. 

Efficient stem cell expansion is a key bottleneck for clinical application and commercialization of stem cell therapy. Membrane bioreactors may make a significant contribution due to its important features such as possibility for uniform chemical and biochemical conditions within the bioreactor, low or even zero hydrodynamic shears, large surface-to-volume ratios, and physical separation between two cell types but allowing biochemical signaling between them. For example, it may be possible to culture the feeder cells on one side of the membrane, while culturing human embryonic stem cells on the other. In this way human embryonic stem cells are not mixed with the feeder cells, which eliminates the need for later difficult separation, but get the biochemical signals from the feeder cells that are necessary to proliferate embryonic stem cells (e.g., Choo et al., 2006 Klimanskaya et al., 2005). 

The classic potentiometric enzyme electrode is a combination of an ion-selective electrode-based sensor and an immobilized (insolubilized) enzyme. Few of the many enzyme electrodes based on potentiometric ion- and gas-selective membrane electrode transducers have been included in commercially available instruments for routine measurements of biomolecules in complex samples such as blood, urine or bioreactor media. The main practical limitation of potentiometric enzyme electrodes for this purpose is their poor selectivity, which does not arise from the biocatalytic reaction, but from the response of the base ion or gas transducer to endogenous ionic and gaseous species in the sample. 

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